The increasing rise in the use of stealth drugs (novel synthetic drugs that were previously or remain analytically/structurally uncharacterised and unclassified by government institutions), is exemplified by synthetic cannabinoid products which incorporate CP 47,497 as the active ingredient. Stealth synthetic cannabinoid (SSC) drug manufacturers can base their choice of active molecular target on scientific literature studies that address the therapeutic potential of CB1 (the CNS cannabinoid receptor) agonists and antagonists. By incorporating novel, analytically uncharacterised compounds with high CB1 receptor affinity into herbal mixtures (packaged under such names as Spice, Yucatan Fire), the manufacturers are able to target drug consumers clandestinely by promoting the material as herbal therapeutics. A problem for governments and drug enforcement agencies is that, even after identifying and banning a new synthetic cannabinoid, the manufacturers can rapidly react to the banning by incorporating a different active analogue into the same or a different herbal product; targeted minor changes in the molecular structure of the known active compound can preserve receptor activity but often produces a molecule whose GC-MS/LC-MS (the commonly applied detection techniques) profile is completely different from the original active molecule. Hence, the new active molecule initially remains unidentified and a further resource intensive and costly chemical analytical study to enable structural characterisation is required. The main active ingredients highlighted in SSC products to date are JWH-018, CP 47,497 and JWH-073 (Uchiyama et al. 2010; Hudson et al. 2010; Dresen et al. 2010). Initial studies of the metabolism of CP compounds have highlighted metabolic processes similar to tetrahydrocannabinol (THC) metabolism, namely ring and alkyl substituent hydroxylation, carboxylation and glucuronidation. As described herein, unless otherwise stated, CP refers to synthetic cannabinoid molecules comprising the unfused bicyclic structure II, in which X is either ethyl, n-propyl or n-butyl, as well as, metabolites thereof

Herbal therapeutics have been analysed using solvent extraction, pre-derivatisation and finally GC-MS analysis in SIM mode (Rana et al. 2010). This method is inadequate for the detection of future and ‘current’ JWH and CP SSCs (it is conceivable that ‘current’ herbal therapeutics, as well as CP 47,497, incorporate CP SSCs that are not yet characterised), requires sample pre-derivatisation, specialist staff for its implementation and expensive equipment. In order to address the problem associated with the cheap and rapid detection of known CP molecules and their metabolites and/or future and associated metabolites based on the CP drug families, the Inventors devised a novel method based on novel antibodies raised from novel immunogens. The antibodies underpin an effective analytical and economic solution to the detection and quantification of current and future CP CB1-active molecules in in vitro patient samples and herbal therapeutics.